SUPPLEMENT. 



THE FAMILIES OF FLOWERING PLANTS 



By Charles Louis Pollard. 



CHAPTER XXY.— Continued. 



Family Bixaceae. Bixa Family. Contains 4 genera and about 20 

 species, mostly tropical, but Amoreuxia, a mallow-Kke herb with large 

 flowers, reaches our southwestern borders. The type of the family, 

 Bixa, consists of the single species, B. Orellana. It is a small tree with 

 broad, cordate leaves, somewhat suggesting those of a poplar, and clus- 

 ters of pink flowers having very numerous stamens and a 2-lobed stig- 

 ma (see Fig. 161). The fruit is a very spiny pod which splits into sev- 

 eral valves when ripe; the seeds have a red, waxy coating, constituting 

 the substance known as arnotto. This is an orange coloring matter 

 used as a dye, and also to impart a color to butter. Since the discov- 

 ery of a method by which it can be prepared synthetically by chemical 

 processes, the value of arnotto has depreciated. 



Family Cochlospermaceae. Shell-seed Family. Contains two or 

 three genera and abous 18 species, most of which are included in Coch- 

 lospermum. They are shrubs or small trees with palmately-lobed, long- 

 stalked leaves, and large yellow flowers in terminal panicles. The chief 

 difference between this family and the preceding lies in the single, un- 

 branched stigma and the downy seeds. Some species of Cochlosper- 

 mum, which is exclusively tropical, yield a variety of gum, while others 

 furnish a yellow dye somewhat similar, but inferior to arnotto. 



Family Koeberliniaceae. Junco Family. Consists of the single 

 genus and species Koehei^linia spinosa, a remarkable shrub of the Rio 

 Grande region in Texas and Mexico. It is apparently quite destitute 

 of leaves, the latter being minute and promptly deciduous. The smooth 

 green branches and twigs taper to sharj) spiny points; the small white 

 flowers, which ar9 borne in umbel-like clusters, have 4 sepals, 4 petals, 

 8 stamens, and a 1-celled ovary becoming a black berry in fruit. 



Family Violaceae. Violet Family. Includes about 15 genera and 

 325 species, of wide distribution. Many of the tropical genera are 

 shrubs or trees, but in temperate climates the plants are mostly peren- 



